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1.
《蒙古秘史》中的野生食用植物研究 总被引:7,自引:1,他引:6
哈斯巴根 《干旱区资源与环境》1996,10(1):87-96
经考证,在《蒙古秘史》中的植物古蒙古名称中,有山荆子、稠李、地榆、鹅绒委陵菜、葱、山韭、山丹和野韭等8种野生食用植物。植物区系及地理分布的研究表明,这些植物在十二世纪蒙古人所采集的地点,即现在的蒙古国肯特山脉地区仍有广泛分布。从民族植物学的研究看,它们在蒙古族民间被用于代粮、野菜、茶用、药用和调味品,比过去的利用有了很大的发展,已成为独特的植物利用文化。本文不仅对蒙古学研究能够提供可靠的依据,而且对寻找新的食用植物种类及其开发利用研究也提供了一些基本资料。 相似文献
2.
I. Vloutoglou B. D. L. Fitt J. A. Lucas 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(6):639-653
Conidia ofAlternaria linicola produced on infected linseed crops were mainly dispersed by wind. The numbers of conidia in the air above linseed crops collected by a Burkard spore sampler were greatest between 1200 h and 1300 h, when the relative humidity was lowest. Although numbers of conidia collected decreased with increasing height within and above the crop canopy, air-borneA. linicola conidia were present up to 80 cm above the crop canopy. Conidia ofA. linicola were transported by wind up to at least 40 m downwind from an artificial line inoculum source, but their numbers decreased with increasing distance from the source. In 1991, 1992, and 1993, the dispersal ofA. linicola conidia above linseed crops followed a seasonal periodicity which was influenced by weather conditions and cultural practices. The greatest numbers of conidia were collected during July, August and early September and coincided with periods favourable for sporulation and with an increase in the incidence of the disease in the senescent crop. Air-borneA. linicola conidia produced on point or line inoculum sources (naturally infected linseed stem debris) were responsible for the spread of the disease in linseed crops. In 1992 and 1993, the disease was first detected downwind from the sources, but by the end of the growing seasons, it had spread in all directions and up to 20 m and 60 m from the sources, respectively. Disease gradients were initially steep near the inoculum sources but they became flatter with time due to the secondary spread of the disease. 相似文献
3.
Comparison of the effects of salicylic acid and ethephon with virus-induced hypersensitivity and acquired resistance in tobacco 总被引:4,自引:0,他引:4
L. C. Van Loon J. F. Antoniw 《European journal of plant pathology / European Foundation for Plant Pathology》1982,88(6):237-256
The induction of a hypersensitive reaction in Samsun NN tobacco by tobacco mosaic virus (TMV) at 20°C leads to the development of both localized and systemic acquired resistance, and is associated with the appearance of pathogenesis-related proteins (PR's) and large increases in peroxidase activity and ethylene production. Salicylic acid (SA) induced a similar resistance in treated plant parts and occasionally also in untreated upper leaves of plants of which three lower leaves had been injected. SA also induced the same four PR's, but these were confined to the treated leaves. Thus, the connection between the presence of PR's and the reduction of TMV multiplication and spread may not be direct.In contrast to TMV, SA did not stimulate ethylene production and hardly increased peroxidase activity. Induction of acquired resistance and PR's by SA developed equally well at 20°C and at 32°C. However, pricking leaves with needles moistened with the ethylene-releasing compound ethephon mimicked TMV infection in inducing acquired resistance and PR's in both treated and untreated leaves at 20°C, but not at 32°C. Ethephon increased peroxidase activity at both temperatures, but only at 20°C dit it induce changes in both the anodic and the cathodic isoenzymes that were similar to those induced as a result of TMV infection. SA induced PR's and reduced TMV multiplication in Samsun tobacco, and inhibited virus spread in Samsun NN at 32°C.These observation indicate that neither the induction of PR's, nor the development of acquired resistance is temperature-sensitive. On the other hand, the effects of ethephon are temperature-sensitive in the same way as the hypersensitive response to TMV. It can thus be hypothesized that ethylene, produced naturally during the hypersensitive reaction of tobacco to TMV, leads to the temperature-sensitive synthesis or release of a presumably benzoic acid-type compound that functions as the natural inducer of PR's and acquired resistance. Although vanillic acid has been shown to accumulate in hypersensitively reacting tobacco leaves, it produced none of the effects of SA, and thus cannot be the natural inducer.Samenvatting Inductie van een overgevoeligheidsreactie in Samsun NN-tabak door tabaksmozaïekvirus (TMV) bij 20°C leidt tot de ontwikkeling van een verworven resistentie die zowel lokaal als systemisch werkzaam is, en gaat samen met het verschijnen van pathogenesis-related proteins (PR's) en sterke toename in de activitieit van peroxidase en de produktie van ethyleen. Salicylzuur (SA) induceerde een vergelijkbare resistentie in behandelde plantedelen en af en toe ook in niet behandelde bovenbladeren van planten waarvan drie onderbladeren waren ingespoten. SA induceerde ook dezelfde vier PR's, maar deze waren beperkt tot de behandelde bladeren. Er bestaat dus geen directe samenhang tussen de aanwezigheid van PR's en de remming van de vermeerdering en uitbreiding van TMV in de plant.In tegenstelling tot TMV stimuleerde SA de ethyleenproduktie niet en verhoogde het de peroxidaseactiviteit nauwelijks. Inductie van verworven resistentie en PR's door SA trad even goed op bij 32°C als bij 20°C. Net als infectie met TMV leidde aanprikken van bladeren met naalden die gedoopt waren in een oplossing van ethefon — waaruit in het blad ethyleen vrijkomt — echter tot inductie van verworven resistentie en PR's in zowel behandelde als onbehandelde bladeren bij 20°C, maar niet bij 32°C. Ethefon verhoogde de peroxidaseactiviteit bij beide temperaturen, maar alleen bij 20°C induceerde het veranderingen in zowel de anodische als de kathodische isoënzymen die vergelijkbaar waren met die welke geïnduceerd werden als gevolg van infectie met TMV. SA induceerde PR's en verminderde de vermenigvuldiging van TMV in Samsun tabak, en remde de uitbreiding van het virus in Samsun NN bij 32°C.Deze waarnemingen tonen dat noch de inductie van PR's, noch de ontwikkeling van verworven resistentie een temperatuurgevoelig proces is. Daarentegen zijn de effecten van ethefon op dezelfde wijze temperatuurgevoelig als de overgevoeligheidsreactie op TMV. Men kan daarom veronderstellen dat ethyleen, dat op natuurlijke wijze geproduceerd wordt tijdens de overgevoeligheidsreactie van tabak op TMV, aanleiding geeft tot een temperatuurgevoelig proces, namelijk de synthese of het vrijkomen van een verbinding, vermoedelijk een benzoëzuurderivaat, dat fungeert als de natuurlijke inductor van PR's en verworven resistentie. Hoewel is aangetoond dat vanillinezuur zich ophoopt in overgevoelig reagerende tabaksbladeren, veroorzaakte deze verbinding geen enkel van de effecten van SA. Vanillinezuur kan dus niet de natuurlijke inductor zijn. 相似文献
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P. Galeffi G. Giunta S. Guida C. Cantale 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(5):479-483
Citrus tristeza virus (CTV) is one of the most destructive citrus virus diseases in the world. The construction of an engineered antibody, EMBL accession number AJ278109, able to specifically recognize its antigen, i.e. the coat protein of CTV, directly on infected plant material without any purification or manipulation of the entire woody plant. The potential uses of this engineered antibody are discussed. 相似文献
6.
黄瓜雌雄株性别苗期化学鉴别方法 总被引:3,自引:0,他引:3
应用BTB(溴麝香草酚蓝 )法、NADH(还原辅酶Ⅰ )法和TTC(氯化三苯基四氮唑 )法对黄瓜雌雄株进行了苗期鉴别 ,结果表明 :雌、雄株提取液加入BTB液后雌株转色快于雄株 ,反应后 5h(小时 )内在 6 30nm处雌、雄株吸光值差异最大 ,是鉴别黄瓜雌、雄株的最佳时期。雌、雄株NADH含量和TTCH含量差异显著。BTB法、NADH法和TTC法鉴别雌雄株其差异显著概率均为极显著 ,BTB法和TTC法对雌、雄株混合群体的鉴别正确率均为 10 0 % ,二者可应用于黄瓜雌、雄株苗期鉴别。而NADH法对混合群体的鉴别正确率仅 71.4%。 相似文献
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不同施氮量及栽培密度对烟叶质量的影响 总被引:6,自引:0,他引:6
设置了不同施氮量及栽培密度对烟叶质量的影响试验.结果表明:在一定范围内,随施氮量增加,烟株长势越好;随种植密度的增加,烟叶产值、产量越高.以施纯N6kg/667m2,移栽密度为110cm×56cm处理的初烤烟叶产值、产量、外观质量等效果最佳. 相似文献
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